These blood tests are used to monitor your health and your response to treatment.
CD4 count This blood test checks your immune system.
CD4% This is similar to the CD4 count but is often more stable.
Viral load This test measures the amount of HIV in a sample of blood.
It shows whether treatment is working, and is sometimes used when deciding to start treatment.
Even rough figures from your previous history are useful and your doctor can provide you with these.
The lowest CD4 count and highest viral load results when you were first diagnosed and before you started treatment are the most important.
1 November 2016